package cn.itcast.context;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

//使用servletContext读取资源文件
public class ServletContextDemo6 extends HttpServlet {

	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		try {
			test1();
		} catch (Exception e) {
			e.printStackTrace();
		}
	}
	
	private void test4() throws IOException {
		//读取webroot目录下的资源
		InputStream in = this.getServletContext().getResourceAsStream("/db4.properties");
		System.out.println(in);
		Properties prop = new Properties();
		prop.load(in);
		
		String driver = prop.getProperty("driver");
		String url = prop.getProperty("url");
		String username = prop.getProperty("username");
		String password = prop.getProperty("password");
		
		System.out.println(driver+":"+url);
	}
	
	private void test3() throws IOException {
		//获取web资源的绝对路径
		String path = this.getServletContext().getRealPath("/WEB-INF/classes/db1.properties");
		FileInputStream in = new FileInputStream(path);
		
		Properties prop = new Properties();
		prop.load(in);
		
		String driver = prop.getProperty("driver");
		String url = prop.getProperty("url");
		String username = prop.getProperty("username");
		String password = prop.getProperty("password");
		
		System.out.println(driver);
	}

	//读取web工程中资源文件的模板代码
	private void test2() throws IOException {
		InputStream in = this.getServletContext().getResourceAsStream("/WEB-INF/classes/db2.properties");
		Properties prop = new Properties();
		prop.load(in);
		
		String driver = prop.getProperty("driver");
		String url = prop.getProperty("url");
		String username = prop.getProperty("username");
		String password = prop.getProperty("password");
		
		System.out.println(driver);
	}

	public void test1() throws Exception {
		//做web工程时，不建议采用传统方式读取文件数据
		FileInputStream in = new FileInputStream("db.properties");
		System.out.println(in);
		Properties prop = new Properties();
		prop.load(in);
		
		String driver = prop.getProperty("driver");
		String url = prop.getProperty("url");
		String username = prop.getProperty("username");
		String password = prop.getProperty("password");
		
		System.out.println(driver);
		
	}

	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		doGet(request, response);
	}

}
